Deaths with Dementia in Indigenous and Non-Indigenous Australians: A Nationwide Study

Abstract

Background: The prevalence of dementia is generally reported to be higher among Indigenous peoples. Objective: The rates and coding of dementia mortality were compared between Indigenous and non-Indigenous Australians. Methods: De-identified individual records on causes of death for all people aged 40 years or more who died in Australia between 2006 and 2014 (n = 1,233,084) were used. There were 185,237 records with International Classification of Diseases, Tenth Revision, codes for dementia (Alzheimer’s Disease, vascular dementia, or unspecified dementia) as the underlying cause of death or mentioned elsewhere on the death certificate. Death rates were compared using Poisson regression. Logistic regression was used to assess whether dementia was more likely to be classified as ‘unspecified’ type in Indigenous Australians. Results: The rates of death with dementia were 57% higher in Indigenous Australians, compared to non-Indigenous, relative rate (RR) 1.57, 95% confidence interval (CI) (1.48, 1.66), p < 0.0001. This excess of deaths was highest at ages below 75 (RRs > 2, test for interaction p < 0.0001), and among men (test for interaction p < 0.0001). When the underreporting of Indigenous status on the death certificate was taken into account the relative rate increased to 2.17, 95% CI (2.07, 2.29). Indigenous Australians were also more likely to have their dementia coded as ‘unspecified’ on their death certificate (Odds Ratio 1.92, 95% CI (1.66, 2.21), p < 0.0001), compared to the non-Indigenous group. Conclusion: This epidemiological analysis based on population level mortality data demonstrates the higher dementia-related mortality rate for Indigenous Australians especially at younger ages.

Volume, scope, and consideration of ethical issues in Indigenous cognitive impairment and dementia research: A systematic scoping review of studies published between 2000-2021

“…Most studies used cross-sectional (n = 34) (Carty et al, 2020; Cotter et al, 2012; Cullum et al, 2018; Garvey et al, 2011; Hocking et al, 2019; Jervis et al, 2007; Kirkpatrick et al, 2019; Lavrencic et al, 2019; Li et al, 2014; Lo Giudice et al, 2011; LoGiudice et al, 2006; Panegyres et al, 2021; Petrasek MacDonald et al, 2015; Pu’un et al, 2014; Radford et al, 2019; Radford, Mack, Draper, Chalkley, Daylight, et al, 2015; Radford, Mack, Draper, Chalkley, Delbaere, et al, 2015; S. Russell et al, 2021; Russell et al, 2016; S. G. Russell, Quigley, Thompson, et al, 2021; Sentell et al, 2015; Smith et al, 2016; Smith et al, 2010; Smith et al, 2009; Smith et al, 2008; Smith et al, 2021; Verney et al, 2008; Wadsworth et al, 2016; Walker et al, 2021; Waller et al, 2021; Weiner et al, 2008; Weiner et al, 2011; White et al, 2019; Whyte et al, 2005) or qualitative (n = 24) (Arkles et al, 2020; Blix & Hamran, 2017; Browne et al, 2021; Bryant et al, 2021; Chen et al, 2019; Dudley et al, 2019; Fife et al, 2020; Finkelstein et al, 2012; Forbes et al, 2013; Gilmour et al, 2016; Hanssen, 2013; Hulko et al, 2010; Jacklin et al, 2015; Jacklin, Pitawanakwat, Blind, Lemieux, et al, 2020; Jacklin, Pitawanakwat, Blind, O'Connell, et al, 2020;…”

“…Studies were mostly conducted in Australia with Aboriginal and/or Torres Strait Islander people (n = 30, see Figure 3) (Arkles et al, 2020; Bryant et al, 2021; Cotter et al, 2012; Cox et al, 2019; Derrig et al, 2020; Dingwall et al, 2017; Garvey et al, 2011; Hocking et al, 2019; Lavrencic et al, 2019; Li et al, 2014; Lindeman et al, 2012; Lo Giudice et al, 2016; Lo Giudice et al, 2011; LoGiudice et al, 2006; Panegyres et al, 2021; Radford et al, 2019; Radford, Mack, Draper, Chalkley, Daylight, et al, 2015; Radford, Mack, Draper, Chalkley, Delbaere, et al, 2015; S. Russell et al, 2021; Russell et al, 2016; S. G. Russell et al, 2021; Smith et al, 2016; Smith et al, 2010; Smith et al, 2009; Smith et al, 2008; Smith et al, 2011; Smith et al, 2007; Taylor et al, 2012; Waller et al, 2021; White et al, 2019). Twenty-three studies were conducted in the United States of America with Native American Indian, Alaskan and Hawaiian people (Browne et al, 2021; Carty et al, 2020; Fife et al, 2020; Jernigan et al, 2020; Jervis et al, 2007; Jervis & Manson, 2007; Kirkpatrick et al, 2019; Korn et al, 2009; Lewis et al, 2020; Martindale-Adams et al, 2017; Mayeda et al, 2016, 2017; Mehta et al, 2008; Sentell et al, 2015; Smith et al, 2021; Verney et al, 2008; Wadsworth et al, 2016;…”

“…An additional 10 studies identified employment of Indigenous staff or community members for data collection, field work or trial coordination (Garvey et al, 2011; Jacklin, Pitawanakwat, Blind, Lemieux, et al, 2020; Jervis & Manson, 2007; Korn et al, 2009; Lo Giudice et al, 2016; Smith et al, 2007; Smith et al, 2008; Smith et al, 2009; Smith et al, 2010; Verney et al, 2008) and one study reported using a cultural advisor (White et al, 2019). No information about Indigenous leadership or involvement were reported for 33 studies (Blix & Hamran, 2017; Carty et al, 2020; Chen et al, 2019; Cotter et al, 2012; Cullum et al, 2018; Cullum et al, 2020; Derrig et al, 2020; Fife et al, 2020; Hanssen, 2013; Jacklin et al, 2013; Jernigan et al, 2020; Jervis et al, 2007; Kirkpatrick et al, 2019; Lewis et al, 2020; Li et al, 2014; Mayeda et al, 2017; Mayeda et al, 2016; Mehta et al, 2008; Panegyres et al, 2021; Petrasek MacDonald et al, 2015; Pu’un et al, 2014; S. Russell et al, 2021; Russell et al, 2016; Sentell et al, 2015; Smith et al, 2021; Wadsworth et al, 2016; Waller et al, 2021; Weiner et al, 2007; Weiner et al, 2003; Weiner et al, 2008; Weiner et al, 2011; Whyte et al, 2005; Wiese et al, 2020).…”

“…Twenty studies did not directly recruit participants. In 17 studies, secondary analysis was conducted of datasets that had already been collected (Carty et al, 2020; Cotter et al, 2012; Cullum et al, 2018, 2020; Jacklin et al, 2013; Li et al, 2014; Mayeda et al, 2016, 2017; Mehta et al, 2008; Panegyres et al, 2021; Petrasek MacDonald et al, 2015; Sentell et al, 2015; Smith et al, 2021; Waller et al, 2021; Weiner et al, 2003, 2007; Whyte et al, 2005) and three studies were implementation studies/case studies that did not report on recruitment of participants (Martin & Paki, 2012; Martindale-Adams et al, 2017; Weiner et al, 2011). Of the remaining studies, many were comprised of heterogeneous samples of participants.…”

“…2016; Sentell et al, 2015;Smith et al, 2021;Wadsworth et al, 2016;Waller et al, 2021;Weiner et al, 2007;Weiner et al, 2003;Weiner et al, 2008;Weiner et al, 2011;Whyte et al, 2005;Wiese et al, 2020).…”